WASHINGTON -- Two things are now likely in the two-man race for the Republican presidential nomination: This will be a marathon, not a sprint, that will run through the GOP's primaries; and it may well be decided at the party's 2012 convention.

While Gingrich has surged into an impressive lead in the national polls, the state-by-state gantlet of caucuses and primaries makes the prospect of an early nomination victory increasingly unlikely. Think of 1976, when Ronald Reagan's bid to deny President Ford the nomination went all the way to the convention, with Ford winning by an eyelash.

Further complicating the nominating battle, a number of states award delegates in proportion to the percentage of each candidate's vote. That plays to Romney's strength because he has the largest campaign war chest to go the distance, while Gingrich's campaign is in debt.

But Gingrich has something that may trump Romney's deep pockets, and that is the growing support and energy of his party's large conservative base, swelled by legions of tea party activists who have rallied to his cause.

On the other hand, besides the support of the party's establishment, Romney has much stronger appeal among independent voters who, polls show, have turned against President Obama in droves. That won't help Romney in the GOP's closed-party primaries, but it could boost his support in some delegate-rich states that have open voting.

Gingrich is the clear favorite to win the Iowa caucuses, where polls show Romney in third place; however, Romney leads the former Georgia congressman in New Hampshire. Gingrich remains unbeatable in South Carolina, yet Florida is up for grabs and Romney has locked up Nevada.

That takes the race deep into February and a long, hard slog through dozens of contests in the spring and summer.

Each comes into this race with strong credentials but also many flaws.

Gingrich, a former history professor, began his political career as a back-bencher who quickly rose up the ranks through his relentless, stinging attacks on the Democrats, eventually driving House speaker Jim Wright from office on ethics charges.

He went into the history books with his brilliant Contract With America campaign in 1994 that put Republicans in control of the House for the first time in 40 years. As the new speaker, he cut spending, passed welfare reform, and persuaded President Clinton to sign a GOP-passed capital gains tax cut, which triggered a surge in economic growth and tax revenue.

But his speakership foundered on his often erratic style and undisciplined focus, which turned the GOP's top House leadership against him in a plot to drive him from power.

A senior aide to Gingrich told me at the time that his boss's biggest fault was that he couldn't stay focused, zigging and zagging on issues and strategy, often popping off with remarks to reporters that got him into trouble and that "drove the top leadership crazy."

Facing rebellion in his caucus after suffering losses in the midterm 1998 elections, Gingrich left the speakership and resigned from Congress in 1999.

Romney has spent most of his career in the business world, founding Bain Capital, one of the largest venture capital investment firms in the country and one that built dozens of businesses into major employers.

He ran for the Senate against Ted Kennedy in 1994 and lost. Then, after rescuing the Salt Lake City Olympics from scandal and bankruptcy in 2002, he won the governorship in 2002.

Despite an overwhelming Democratic legislature, he eliminated a $3 billion deficit, established a rainy day fund, and enacted a near-universal health care law with the help of the conservative Heritage Foundation.

Romney has changed his mind on some issues -- as Gingrich has from time to time -- but he is the opposite of Newt in terms of temperament, discipline and focus.

He is running on his lifelong executive experience and his knowledge of economics, business and creating jobs at a time when America is in a steep economic decline.

If Romney has a weakness, it is his tendency to play it safe. His reform agenda on spending and tax cuts doesn't promise more than he believes he can deliver. The weak Obama economy suffers from a lack of private investment in business expansion. But Romney limits his capital gains tax cut to the middle class, instead of an across-the-board cut that would yield the most bang for the buck.

In that sense, Gingrich is more of a political risk-taker. He took a big chance of alienating his party's conservative base when he proposed giving some level of legal status to illegal immigrants who've lived here for 25 years or more.

Some strategists predicted he would lose much of his conservative base on that issue, but in fact his support has only grown.

Gingrich was left for dead earlier this year when his senior staff resigned in frustration after he went on a cruise of the Greek Islands with his wife, Callista, just as his campaign was getting off the ground.

His performance in debates has pushed him to the top of the field, but he has no national campaign organization to speak of, and he plunged his early campaign deeply into debt by flying in private jets and staying in plush hotel suites.

The Washington Post reported Thursday that his Iowa campaign headquarters appeared nearly empty this week, with only two volunteers -- an out-of-state mother and a grandmother making phone calls.

Romney has begun running ads and cautiously beefing up his presence in the state, while focusing on what senior strategists have always believed will be a long and steady race with no clear winner until they call the convention delegate rolls in Tampa next August.